As a means for detecting a vehicle collision and the like, there is a load sensor using optical fiber (for example, see Patent Document 1). In a load sensor of this type, when the optical fiber deforms due to a collision, loss of light transmitting from one end to the other end of the optical fiber becomes greater. Based on this loss of light, whether there is a collision is judged. The optical fiber is attached to a resin retaining plate.
On the other hand, the present applicant has proposed a load sensor having an elastomeric sensor thin film (for example, see Patent Documents 2 and 3). In a load sensor disclosed in Patent Document 2, a sensor thin film is formed in which conductive filler is filled in elastomer of a parent material at a predetermined state. According to this load sensor, based on a change in electrical resistance caused when the sensor thin film elastically deforms, an input load can be detected. A load sensor disclosed in Patent Document 3 is a capacitance-type sensor, which includes an elastomeric dielectric film and a pair of electrodes arranged sandwiching the dielectric film. According to this load sensor, based on a change in capacitance between the pair of electrodes, an input load can be detected.